Note: Descriptions are shown in the official language in which they were submitted.
` ~06~3~G
The presen-t invention relates to 2-cyano-3 or 4 (sub-
stituted amino) oxanilic acid derivatives having pharmacological
activity.
Atopic allergic reactions are of the immediate
hypersensitivity type as opposed to delayed hypersensitivity
reactions, the latter being involved in such things as tuberculin
sensitivity, transplant rejection, contact dermatitis and the
like. Commonly recognized clinical conditions known to be at
least in part due to atopic immediate hypersensitivity reactions,
include seasonal and perennial allergic rhinitis (hay fever)
.... .
and asthma, anaphylaxis, urticaria, conjunctivitis, angioaedema,
eczema, various food and drug reactions and insect sting
reactions. The substances most frequently responsible for atopic
allergic reactions are plant pollen, animal feathers and danders,
dust, milk and wheat, whether inhaled or injested. Atopic
hypersensitivity is found in man, dog and other animals although
its occurrence is exceptionally found in the lower animals.
Atopic (immediate hypersensitivity) reactions are
characterized by the immunopathologic mechanism, the elements of
which are: (1) a specific immunoglobulin ~antibody: IgE in man,
or homocytotropic antibody in the rat) is produced; (2) it is
fixed to the surface of a target cell; (3) an antigen or allergin
combines with the cell-bound antibody, which(~) induces release
of one or more
,
~ ,
~ 1 -2- i
pharmacologic mediators, which in turn (5) induces symp-
toms of clinical disease such as increased vascular perme-
ability, smooth muscle contraction, mucous gland hyper- ;
secretion, leukotaxis (especially eosinophilotaxis) and
irritation of sensory nerve endings~
A compound which will interfere with the antigen-
IgE reaction to prevent the release of medialtors from the
.: .. . . .
ma~t cell, or permit a non-productive antigen-antibody
reaction without release of mediators, of necessity blocks
the atopic allergic reaction thereby avoiding the resultant
changes which are symptomatic of the disease.
The presence of antibodies associated with atopic
reaction~ in the host serum is established by the passive
sensitization of the skin of a normal recipient, after in-
jection of serum from a sensitized host into a skin ~ite
followed by injection of antigen into the same area 2~ hours
later, resulting in a local hive. This is commonly referred
to as the Prausnitz-Kustner (P-K) reaction.
The antibody associated with atopic hypersensiti-
vity possesses distinctive features in that it does not in
all forms precipitate with its antigen, fails to pass the
placenta from mother to fetus, has special affinity for the
skin, frequently lacks specificity toward an individual
antigen in an ~ndividual sensiti~ed by a variety of antigenic
factors and is usually labile at about 56 C. after two
hours.
The homocytotropic antibody found in or induced
in the rat is related in function and reaction to immuno-
globulin E (reagin or IgE) found in the human. The cor-
relation between homocytotropic antibody in the rat and IgE
3 - ;
. .
. .
36~3S6 ~
in the human has been established through the common
effects obtained from chemical reactions, immunological
reactions and drug responses in the two species hosting
those antibodies. In the human, reagin is the antibody
responsible for atopic immediate hypersensitive reactions.
In the rat, the homocytotropic antibody is responsible for
atopic immediate hypersensitive reactions.
In theory, reagin influences the cell membrane `
of a mast cell by reacting with an antigen, to initiate the
reaction(s) within the mast cell which ultimately releases
a mediator such as Bradykinin, SRS-A (slow reacting sub- ;
stance-A), histamine, and other unknown substances. The
mediator effects a change in surrounding cell wall permea-
bility permitting a rapid change in flow or exudance of
mediator(s) from the cells, resulting in an allergic attack
symptom. The various methods commonly employed to relieve
the symptoms of allergic attack, none of which are consi-
dered to be quite acceptable, are to (1) avoid attack by ~'!
the antigen, (2) block the production of antibody with an
immunosuppressant, (3) block the action of the mediators
on the cell under attack b~ administration of anti-hista-
mines, anti-5-hydroxy-tryptamine (5-HT) or anti-inflamma-
tories, or (4) stimulate and cell under attack to negate
the action of the mediator through the action of bronchodi-
lators such as Isoprel~ or a Xanthine.
The only commercial compound known to date to op- ;
erate as an anti-allergic primarily by blocking reaction(s)
within the mast cells, thereby preventing the production
and release of mediators, is disodium cromoglycate (INTAr~
Disodium cromoglycate and compounds of that class
are preventative in the sense that they must be adminis-
,''
.
~!~613~6
tered to the sensitized animal prior to the allergic attack to
,," : .,
be effective. They are not effective after the mediators have ;,
been released from the mast cells. Hence, their function is
in preventing the release of mediators and/or a productive
antibody-antigen reaction. As such, the rat PCA test ~measur-
ing the effect of mediator release) may be used to establish
a compound as effective for all atopies because it establishes
the diminished mediator release values in terms of the de-
crease in allergic response of the animal. The rat PCA test
establishes the extent of mediator release from mast cells
located in the rodent skin as a factor of the diminished effect
on the skin of the test animal in relationship to the con-
trol animals.
The rat PCA (passive cutaneous anaphylaxis) test
provides a classic procedure for e~aluating the efficacy of
drugs of the INTAL class relative to the response of the
standard test animal resulting from antigen antibody inter-
action and mediator release. Extrapolation from an effect
on the homocytotropic antibody of the rat to an effect on ;~
reaginic antibody (IgE) in the human is proper because of ;
the well established relationship between these antibodiesO
With knowledge of the mechanism of activity of `~
INTAL in blocking the production of chemical mediators re- `
sulting from an antigen~antibody reaction and the variety
of confirmed activities of INTAL in controlling or prevent-
ing immediate hypersensitivity reactions in man, as well as
the close relationship between the rat homocytotropic anti-
body and IgE in the human, coupled with the fact that INTAL
is the standard now used in the field for evaluating the
efficacy of new anti-allergic compounds for atopic allergic
_ 5 -
'
3S6
reaetions via the rat P~A test must lead to the practical
conclusion that compounds which are active in the rat PCA
test can, with very reasonable assurance, be projected as
active anti-allergie agents in ma~, dog, etc.
As new anti-allergics are being developed, their
activity mechanism is related to that of INTAL as the stan-
dard because of its known activity in man and its activity
in the rat PCA test. In this regard see Pfister et al.,
JO Med. Chem., vol. 15, No. 10, pp. 1032-1035 (1972);
Broughton et al., Nature, vol. 251, pp. 650-652, October 18,
1971; and Assem et al., British Med. Journal, April 13,
197~, pp. 93-95.
DESCRIPTION OF THE INVENTION
In aeeordance with this invention, there i~ pro-
vidod a group of ehemieal eompounds, useful for inhibiting
development of the physieal symptoms attending an atopic
allergie reaetion, presenting the formula: -
'
Rl R2 ..
N
CN
~ N~ICOC02R
in which -
R is -H; an alkali metal; +NH4; alkyl of 1 to 6
carbon atoms, inclusive; aralkyl of 7 or 8
carbon atoms; or cyeloalkyl of 5 or 6 earbon
atoms;
R is -H or alkyl of 1 to 9 carbon atoms;
R is -H, alkyl of 1 to 9 carbon atoms or eycloalk~l
of 3 to 6 carbon atoms;
'` ~ '
. '~ ~' '
- 6 - ~
356
and -`
Rl and *, together with the nitrogen atom to which
they are attached, are aziridinyl, azetidinyl,
pyrrolidinyl, piperidinyl, piperaz;inyl, 4-lower
alkyl-pipera~inyl, morpholino or thiomorpholino~
and pharmaceutically acceptable acid addition salts
thereof.
In the preeeeding formula, the alkali metals co~- ;
templated for the group "~", ~re sodium, potassium or lith~
iumO Embraced by the expression "alkyl o 1 to 6 carbon
atoms" are such alkyl groups as methyl, ethyl, n=propyl, i-
propyl, n-butyl, secondary bu~yl, tertiary butyl, pentyl ;
and hexyl. The expression "aralkyl of 7 or 8 carbon atoms"
is intended to embrace the benzyl and phenethyl radicals.
The contemplated cycloalkyl groups of 5 or 6 carbon atoms
embrace cyclopentyl as well as cyclohexyl. The groups
representing R~ and R2 may be normal or secondary alkyl ~;
containing from 1 to 9 carbon atoms each. Where Rl and R2
represent a cyclic group with the nitrogen atom depicted in
the structwral formula, they are represented as dimethylene,
trimethylene, tetramethylene, pentamethylene, or the 3-oxa,
aza, or thia-pentamethyle~e radicals (oxy, thio or imino
di-ethylene). In those situations where Rl and R2 repre-
sent a heterocyclic group containing ni$rogen, it is pre-
ferred to prepare the compounds in the form of their non- ~ -
toxic pharmaceutically acceptable acid addition salts for
the purpose of separation and recoveryO Likewise, when
Rl and/or R2 is hydrogen, that amino group is proteeted
during reaction with the chloro oxalic acid ester follolwed
~0 ultimately by removal of the protecting group. For this
purpose, any standard protecti~g group known to the art
,. . .
- 7 - ~
~-? ~:~
10613S6
may be employed, the trimethylsilyl group being represen-
~ative of the type of protecting group especially suitable
for the purpose stated.
The expression, pharmaceutically acceptable acid
addition salts, is used to include the non-toxic acid ad-
dition salts which may be formed with either organic or
inorganic acids such as hydrochloric, hydrobromic, sulfuric,
phosphoric, methane sulfonic, nitric~ p-toluene sulfonic,
acetic, citric, maleic, succinic acid and the like.
The pref~rred compounds from the sta~dpoint of
potency are those in which Rl a~d R2 are hydrogen or Rl is
lower alkyl and R2 is hydrogen and the amino group ~ 1
-N
~,
is in the 3-position.
The 3- or 4-substituted-2-cyanooxanilic acid com-
pounds o this invention are generally produced by condens- ` i
ing an appropriately substituted 2-cyanoaniline w~th an ac-
tivated oxalic acid half ester in which the substituent in
.
3- or 4-position is amino, alkylamino of 1 to 9 carbon `~
atoms, dialkylamino of 1 to 9 carbon atoms in either alkyl
moiety, cycloalkylamino of 3 to 6 carbon atoms, aziridinyl,
azetidinyl, pyrrolidinyl, piperidinyl, piperazinyl, 4-
lower alkyl-piperazinyl, morpho:Lino or thiomorpholino.
;, ,
By an activated oxalic acid half ester, applicants embrace
the acid halides, mixed anhydrides, azide, and the like ~ -
groups employed in the production of amidic linkages. -
The 2-cyano group may be formed optionally via f;. . ;~
dehydration of a correspondingly 2-carbamyl ~ubstituted
precursor. Further more, a free amino group in 3- or 4-
position may be produced ~y reduction of a nitro substi- ;
tue~t after condensation with said activated oxalic acid
''" '" ':~.
- 8 - ~
.. , ,.. , .... . , ~ . .. . ~ ,, .. , ... . ., ............. ,,, . .. :, :.
~06E;~356 :
... `~ `
half ester. The free amino group may be then mono- ~`
or dialkylated with groups which are optionally cyclizable. `
Likewise, the final product ester is saponified with an
appropriate base to afford an alkali metal or ammonium
salt.
:.~. - .
The compounds of this invention have been
demonstrated to relieve allergic manifestations when
administered intraperitoneally and/or orallg to sensitized
rats.
,. . .
The technique employed to establish the anti~
allergic activity of the disclosed compounds is reported
in Immunology, vol. 16, pp. (749-760 (1969) and invol~es -
four male Charles River rats (200-250 g. body weight) per
group to provide a control, a host for adminis~ration of a
standard anti-allergic compound (disodium cromoglycate)
and animals for the test compound. The rats are injected
intracutaneously or their shaved backs with sera from rats
immunized with egg albumin and pertussis vaccine. Twenty-
four hours after the initial injections, the test compound
is administered intraperitoneally or orally at a m~ximum
dosage level of 200 milligrams per kilogram host body
weight. Five minutes later one milliliter of a 0.5 percent
solution of Evans blue dye and 8 milligrams of egg albumin
is injected intravenously. Ater forty minutes, the animal
is sacrificed and the bleb size on its back is measured.
The mean bl!ëb size for the animals administered the test
compound is calculated and the percent inhibition is deter-
miIled by comparison with the control animal.
Although the mechanism by which the compounds of
this invention function is not absolutely known, applicants
have found that the compounds of this invention, in a man- `
_ 9 _ ,
3S6
ner believed to be similar to the function of INTAL, block ~`
reaction(s) in the mast cell leading to the production and
release of media~ors. The compounds of this inventio~ per-
mit the occurrence oL a non-productive antigen-antibody
interaction by effectively blocking the Ig~ type reaction.
In sum, the compounds of this invention block the release
of mediators commonly resulting from the a~tigen antibody
,. i
reaction as exemplified in a passive cutaneous anaphylaxis
test ~PCA) using rat homocytotropic antibody--a known cor-
relate of human reaginic antibody.
By analogy to disodium cromoglycate and its acti-
vity correlation between standard tes-t animals, domestic
animals and man, the compounds of this invention have been
established as anti-allergic agents suitable for use as in-
halants or by oral or parenteral administration.
Thus, the compounds of this invention are useful
for suppressing allergic manifestations of atopic immediate
sensitivity in warm-blooded human and non-human animals,
the latter including domesticated animals such as the
mouse, rat, hamster, gerbil, dog, cat, sheep, goat, horse,
cow, and the like, by administering an effective amount of
one or more of the compounds disclosed in this application i
by oral, topical, intraperitoneal, intramuscular or intra- `
venous routes. The compounds of this invention may be ad-
ministered in coniunction with known compounds effecting
antihistaminic, anti-hypertensive, analgesic, central ner-
vous s~stem depressant, immunosuppressive, anti-serotonin,
anti-Bradykinin or endocrinological responses. In addition,
those conventional adjuvants known to the art may be com-
bined with the anti-allergios of this invention to provide
eompositions and solutions for admi~istrative purposes,
:
.:
.. -- 10 -- ~ '
, ~
-
~06~L356
although it is considered desirable and feasible to employ
the anti-allergics as neat or pure compounds without addi-
tives other than for purposes of pro~iding suitable pharma-
ceutical solution or liquid or vapor suspensions.
The effective dose range in test animals has been
established to be from about 0-01 mîlligrams per kilogram r
to a dosage resulting in substantially 100 percent preven-
tion of the allergic response at 200 milligrams per kilo-
gram host body wei~ht, or less.
As an inhalant, the dose is two milligrams or
less, administered as needed prior to attack. Thus, the ~-
dosage contemplated for human oral or intraperitoneal use
based upon the potency of the compound administered lies
from about 1 milligram to 2 grams, preferably 5 milligrams
to about 1.5 grams in unit dosage form to be administered
when necessary and to the degree of the desired response,
in single or plural doses ~nder the guidance of a p~ysician.
Regarding the dosage to be used in the treatment
o~ a specific atopic allergic reaction, the subjective
2Q observations of the attending physician are determinative.
The human dose, like the dose for the dog, depends upon the
speci~ic allerg~ being treated, the size, age, response
pattern and severity of the known allergic attack in the
specific patient. No unusual skill is involved in estab-
lishing the most desirable dose size and regimen for a spe-
;: .
cific patient because the loss or supp~ession of the symp-
tom is apparent to both the patient and the physician.
The effective amount of the anti-allergic compound admin-
istered must be empirically determined subjectively.
Illustrative of the compounds of this invention,
which are orally active are 2-cyano-3-(dimethylamino)o~a-
,
~L~96~35~; `
nilic acid ethyl ester, demonstrating oral activity equi-
valent to 5~% inhibition at 5 milligrams per kilogram host
body weight; 67% inhibition at 2~ milligrams per kilogram
host body weight and 73% inhibition at 100 milligrams per
kilogram host body weight, as well as 2-cyarlo-3-(4-methyl-
l-piperazinyl)oxanilic acid ethyl ester hydrochloride which
effects a 77% inhibition upon oral administration of 25
milligrams per kilogram host body weight. Illustrative of
the compounds of this in~ention possessing anti-allergic
activity upon intraperitoneal administration is 2-cyano-3-
(l-piperidinyl)oxanilic acid ethyl ester which affords 93% ;
inhibit~on at 200 milligrams per kilogram host body weight;
the two compounds mentioned in the preceding sentence pre-
senting, respectively, 93% inhibition at 200 milligrams per -
kilogram host body weight and 88% inhibition at 200 milli-
grams per kilogram host body weight. hs noted suPra, the
,. . .
preferred compounds as those in which the amino group ap~
pears in 3-position as the free amino group or lower alkyl-
amino group. These compounds have been found to effect
100% inhibition with as low as 0.10 milligrams per kilo-
gram dosage administered intravenously with the sodium salt
of ~2-cyano-3-(methylamino)phenylamino~oxoacetic acid.
' ~ "`~;
.`. ~ ~, .
"., ~ .
- 12 -
r.~ . .
~ -
56 `;
Example 1
[2-Cyano-3-(Dimethylamino)Phenylamino]-
_ Oxoacetic Acid Eth~l Ester
To a solution of 9.7 g. of 2,6-dinitrobenzoni-
trile and 6.1 g. of dimethylamine hydrochloride in 100 ml.
of dimethylformamide is added 6 g. of potassium hydroxide
in 20 ml. of water. me solution is stirred for 4 hours,
poured into ice water and the product, 2-dimethylami~o-6-
nitrobenzonitrile, is filtered and dried, m.p. 112-116C.
Analysis for: CgHgN302
Calculated: C, 56.54; H7 4.75; N, 21.98
Found: C, 56.28; H, 4.77; N, 21.77
,`
To a suspension oP 5.7 g. of 2-dimethylamino-6-
nitrobenzonitrile in 20 ml. of meth~ol and 17 ml. of con-"A'~
centrated hydrochloric acid is added 5.3 g. of iron powder -
in portions. The mixture is stirred for 1/2 hour, diluted -
with 200 ml. of water and extracted with methylene chloride
which is dried and evaporated in vacuo to yield crude 2- `
amino-6-dimethylaminobenzonitrile.
To a solution of 3~4 g. of crude 2-amino-6-di-
methylaminoben~onitrile and 1.6 g. of pyridine in 50 ml. of
m¢thylene chloride at 0 is added dropwis¢ 2.7 g. of ethyl
oxalyl chloride in 25 ml. of methylene chloride. The solu-
tion is stirred at 0 C. for 3 hours, warmed to room tem- --
perature a~d water is added. The organic phase is separated, -
dried a~d evaporated to give a yellow solid which is re-
crystallized~r-o~ benzene hexane to yield 3~2 g. of the ti-tle
compound, m.p. 124-126Co ~. . .
, ~; . .
Analysis for: C13~15N303
Calculated: C, 59.76; H, 5.79; H, 16.08 ~ '
Found: C, 59,47; H, 5.47; N, 16.08
:
- ~3 -
' ~LQ6~356 ~ i
Example 2
[2-Cyano-3~ Piperidinyl)Phenylamino~-
_ Oxoacetic Acid_Ethyl Ester
To a solution of 19.3 g. of 2,6-dinitrobenzoni-
trile in 300 ml. of dimethylformamide is adlded 25.5 g. of
piperidine and the resulting solution is warmed to 85 C.
and kept at that temperature until the reaction is complete.
The reaction mi~ture is poured into water, the product, 2- ;~
nitro-6-(1-piperidinyl)benzonitrile, is filtered and dried,
m.p. 119-121C.
,~.. . ..
Analysis for: C12H13N30
Calculated: C, 62.32; ~I, 5.67; N, 18.17
Found: C, 62.32; H, 5.82; N, 18.26
The 2-nitro-6-(1-piperidinyl)benzonitrile pre- ;;
~... : .
pared in the preceding paragraph is converted to 2-amino-6-
(l-piperidinyl)benzonitrile by iron reduction following the -
procedure of Example 1. `;
The title compound is produced by reaction of 2-
amino-6-(1-piperidinyl)benzonitrile with ethyl o~alyl chlo-
ride, m.p. 98-100C.
Analysis for: C16HlgN303
Calculated: C, 63.77; H, 6.36; N, 13.94
Found: C, 63.76; H, 6.37; N, 13.76 ~`
~.
E~ample 3
C2-Cyano-3-(4-Methyl-l-Piperazinyl)Phenyl~mino]Oxacetic ;~
_ _ Acid Eth~l Ester H~drochloride ~
Following the procedure presented in the first
paragraph of Example 2, with the e~ception that N-meth~l-
. . .
piperazine is substituted for piperidine, 2-(~-methyl-]L-
piperazinyl)-6-nitrobenzonitrile is prepared, m.p. 126 129
C. ',,' .
' ~. . ' .
~6~3~
Analysis for: C12H14N402
Calculated: C, 58052; H, 5.73; N, 22.75
Found: C, 58.65; H, 5.87; N, 22.78
To a solution of ~.92 g. of 2-(4-methyl-1-piper-
azinyl)-6-nitrobenzonitrile in 11 ml~ of concentrated hydro-
chloric acid is added 3.4 g. of iron powder~ The mixture
is stirred for 30 minutes, poured into ice water and the p~ `r
~`
is adjusted to 12~ Methylene chloride is added, the whole
mixture is filtered through celite, the methylene chloridle
is separated, dried and evaporated to give solid, crude `- `
product, 2-amino-6-(4-methyl-1-piperaæinyl~benzonitrile.
A mixture 3.96 g. of crude 2-(4-methyl-1-pipera- ;
zinyl)-6-aminobenzonitrile, 2.74 g. of eth~l oxalyl chlo-
ride is ~tirred for 2 hours at room temperature, poured
into 1.68 g. of sodium bicarbonate in 25 ml. of water and
stirred for 5 minutes. The organic layer is separated,
:: .
dried and evaporated. The residue is dissolved in diethyl
ether-ethanol, saturated diethyl ether-hydrogen chloride is
added and the product is allowed to crystallize to give the
pure title compou~d, m.p. 204-206C. (dec.).
Analysi9 for: Cl6H20N4o3 HCl
Calculated: C, 54.56; ~I, 6.00; N, 15.88; Cl, 10.05
Found: C, 54.53; H, 6.31; N, 15.90; Cl7 10.08
Following the general preparative procedures ;-
.. . .
exemplified in the preceding examples, by var~ing the amine
reactant (HNRlR2) employed in the displacement reaction
with 2,6-dinitrobenzonitrile, reducing the remaining nitro
~.
substituent to afford the reactive amino group ~nd finally
coupling that produc$ with ~n oxalyl chloride ester~ there
is afforded a family of 2-cyano-3- or 4-~substituted amino)-
oxanilic acid esters which may be directly saponified to
,h,
- 15 - ~>~
.,
afford a salt, or readily hydrolyzed under mild conditions
to yi~ld the c~rresponding oxanilic acids which are in turn
readily converted to the corresponding salts upon reaction
with a desired base.
Vario~s amines, HNRlR27 employed in the ~yn~hesis
of the anti-allergic compounds of this in~e:ntion and the
final products, employing ethyl oxalyl chloride in each
instance as representative of the simple oxalyl ester reac- :~
tants employed in the synthesis, are: ~;
N~lR2 - :
Rl R2 ~ 1 Ester of
1. -H -C~I3 2-cyanow3-~methylamino)
oxanilic acid
2. -OEI3 -CH3 2-cyano-3-(dimethyl
amino)oxanilic acid .i
3. -CH -CH ~ C~I3 2-cyano-3-(isopropyl- ~ :.
3 ~ methylamino)oxanilic
~ CH3 acid .~
4. -~I CH2C 3 2-cyano-3-(ethylamino) :~ : oxanilic acid :
5. -CH CH -CH CH CH2C~I3 2-cyano-3-(eth~lbutyl- :
2 3 2 2 amino)oxanilic acid
6. -H OEI 2-cyano-3-(sec-butyl-
1 3 amino)oxanilic acid . :
-~HOEI2CH3 ',``: ' ' .
7- CH~CH2CH2~I3 -CH2C~I2CH2C~l3 2-cyano-3-(dibutyl- . .: .
~ amino)oxanilic acid .. :
8. -~I heptyl 2-cyano-3-(heptyl- ::
amino)oxanilic acid
9. -H hexyl 2-cyano-3-(hexyl~ -
C~I3 amino~oxanilic acid
10. -H c~2~ 2-cyano-3-(isobutyl- ..
CH amino)oxanilic acid
3 i~ :
' :
.... .....
. J
- 16 -
.
~ 6~356
R~
/ ~ Final Produet
R2 Ethyl Ester of
11. l-pyrrolidinyl 2-cyano-3~ pyrrolidi-
nyl)oxanilic acid -
12. l-piperidinyl 2-eyano-3-~(piperidirlo)-
o~anilie aeid
13. 4-methyl-1-piperazinyl 2-cyano-(4-methyl- 1-
piperazinyl)oxanilic
acid -
14. morpholino 2-eya~o-3-(morpholino)- ~`
oxanilie aeid
15. thiomorpholino 2-cyano-3-~thiomorpho- ;-
lino)oxanilic aeid
16. l-azetidine 2-cyano-3-(l~azetidi-
nyl~oxanilie aeid ;
17. l-aziridine 2-eyano-3-(1-aziridi-
nyl)oxanilie aeid
Example 4
~2-Cyano-4-(Dimethylamino)Phenylamino]
Oxoacetie Acid Ethyl Ester
To a solution of 4.6 g. of ~2-(aminocarbonyl)-4- S~
..~. . . ..
(dimethylamino)phenylamino]oxoaeetic aeid ethyl ester in ~; ' f
130 ml. of ehloroform at 0C. is added 2 ml. of phos~
phorus oxychloride and 13 ml. of triethylamine. The reac-
tion is stirred at room tempera~ure until eomplete (ap-
proximately 6 days). Water is added, the p~I is adjusted to
about 5 and the organic layer is separated, dried and eva
porated. The produet i~ reerystallized from ethanol, m.p.
150-15~C.
Analysis for: C13HlsN303
Caleulated: C, 59.76; H, 5.79; N, 16.08
Found: C, 59.76, H, 6.02, N, 15.91
,
- 17 - ~.
.
~6~356 ;`: :
[2-(Aminocarbonyl)-4-(dimethylamirlo)phenylamino]
oxacetic acid ethyl ester is prepared by oxalation OI 2-
amino-5-dimethylaminobenzamide with ethyl oxalyl chloride
as in Example 1, m.p. 203-205VC.
Analysis for: C13H17N304
Calculated: C, 55.90; H, 6.14; N, 15.05 ;`
Found: C, 56.12; ~I, 6.23; N, 15.08
2--Amino-5-dimethylaminobenzamide is obtained b~
treatment of 5-dimethylaminoisatoic anhydride hydrochloride
with lN ammonium hydroxide in a manner similar to the pro-
cedure OI R. P. Staizer and E. C. Wagner, J. Org. Chem.,
3, 347 (19~8).
5-Dimethylaminoisatoic anhydride hydrochloride is
obtained by treatment of the corresponding anthranilic acid
with pho~gene in a manner identical to that given in J. H.
Sell~tedt et al., J. Med. Chem., 18 926 (1975) for 3,5-
dimethyl anthranilic acid, m.p. 256-258 C. (dec).
Analysis f~r: CloHloN203 HCl
Calculated: C, 49.49; H, 4.57; N, 11.55; Cl, 14.61
Folmd: C, 49315; ~I, 4.54; N, 11.10; Cl, 14.57
5-Dimethylaminoanthranilic acid is known, R. A.
Rossi alld H. E. Bertorello, An. Assoc. Quim. Argent., 55,
227 (1967).
E~ample 5
[3-Amino-2-Cyanophenylamino]-
(~xoacetic Acid Ethyl Ester _
The title compound is prepared by reduction of i
[3-nitro-2-cyanophe~ylamino]oxoacetic acid ethyl ester with
10% Pd. on charcoal and with cyclohexene in ethanol accord~
ing to the procedure of I. D. Entwistle alld R. A. W.
- 18 -
~06~356 ~:
Johnstone, J. Chem. Soc., Perkin I, 1300 (1975). The crude
product is chromatographed on silica gel with chloro~orm
and recrystallized fr-~m ethanol, m.p. 133-136 C.
Analysis for: CllHllN303
Calculated: C, 56.64; H, 4.76; N, 18.02
Found: C, 56.58; H, 4.64; N, 18.20
[3-Nitro-2-cyanophenylamino]oxoac0tic acid ethyl
ester is prepared by treatment of 2-amino-6--nitrobenzoni-
trile with ethyl oxalyl chloride as in Example 1, m.p.
111-113C. ~ -
Analysis for: CllHgN305
Calculated: C, 50.19; H, 3.45; N, 15.97
Found: C, 50.11; H, 3.44; N, 15.99
2-Amino-6-nitrobenzonitrile is prepared as follows: i ~
2,6-Dinitrobenzonitrile (19.3 6 ) is dissolved in i ;
methanol (400 ml.) and dioxane (250 ml.) at reflu~. To this
is added conc. hydrochlorio acid (60 ml.) follo~ed by iron ~! ,
powder (18 g.) in portions. The mi~ture is left at reflux
for 1 hr., and is evaporated to drynes~. Water is added,
the resultant solid is filtered off, dried and extracted
with hot ethyl acetate. After filtration through Celit~ ,
the product i9 allowed to crystallize, m.p. 196~198C.
~nalysis for: C7H5N302
Calculated: C, 51.54; H, 3.09; N, 25.76
Found: C, 51.39 7 H, 3.01; N, 25.68
Example 6
[3-(Methylamino)-2-Cyanophenyl~mino]-
_ Oxoacetic Acid Et~l Ester
Oxalation of 2-amino-6-methylaminobenzonitrile
as in Example 1 gi~es the title compound, m p. 137-139C.
- 19 -
;
, ".
. . .~
~ \ ~;
~6~L3S6 :- -
Analysis for: C12~I13N303
Calculated: C, 58.29; H, 5.30; N, 17.00
Found: C, 58.13; Hs 5.32; N, 16.94
2-Amino-6-methylaminobenzonitrile is prepared by
iron reduction of 2-methylamino-6-nitrobenzonitrile as in
Example 1.
2-Meth~lamino-6-nitrobenzonitrile is prepared
as follows:
to 19.3 g. of 2,6-dinitrnbenzonitrile in 150
ml. of dimethylform~mide at 85C. is added 25 ml. of
40% aqueous methylamine. The mixture is heated for 1
hour, poured into ice water and the product is removed by
filtration~ m.p. 203-206C.
,. .
Analysis for: C8H7N302
Calculated: C, 54.23; H, 3.99; N, 23.72
Found: C, 54.24; H, 3.70; N, 24.02
Example 7
~2-Cyano-3-(Ethylamino)phenylamino]-
Oxoacetic Acid Ethyl E~ter
Crude 2-amino-6-ethylaminobenzonitrile is
, :.:
oxalated as in Example 1 to give the title compound,
m.p. 99-102C.
Analysi~ for: C13~ll5N303
Calculated: C, 59.76; H, 4.79; N, 16.08
Found: C, 59.35; H, 5.89; N, 15.88
Crude 2-amino-6-ethylaminobenzonitrile is pre-
pared by iron reduction of 2-ethylamino-6-nitro-benzo-
nitrile as in Example 1.
2-ethylamino 6-nitrobenzonitrile is obtained by
displacement on 2,6-dinitrobenzonitrile with ethylamine
..;. ,
as in E~ample 6, m.p. 114-116Co
;; ... :. '
- 20 - ~
.. . . . .
~L~6~3~6
Analysis for: C9HgN30~
Calculated:C, 56.54; H, 4.75; N~ 21.98
Found:C, 56.73; H, 4.75; N, 21.73
. ~ .
Example 8
~3-(Butylamino)-2-Cyanophenylami3no]-
Oxoacetic Acid Ethyl Ester
This material is prepared following the procedure
of Example 1, by oxalation of 2-amino-6-butylaminoben~onitrile, `j -
m.p. 101-105C.
Analysis for: Cls~lgN303
Calculated: C, 62.26; H, 6.62, N, 14.52
Found: C, 62.03; H, 6.~2; N, 1~.55
2-amino-6-butylaminobenzonitrile is obtained b~
iron reduction a~ in Example 1.
2-butylamino-6-nitrobenzonitrile is o~tained by
the usual displacement reaction using butylamine, m.p.
72-74C.
Analysis for: CllH13N
Calculated: C, 60.26; H, 5.98; N, 19.15
Found:C, 60~38; H, 6.09; N, 19.06
Example 9
C3-(Ethylmethylamino)~-2-Cyanophenylamino~-
_ Oxoacetic Acid Ethyl E~ter
Treatment of 2-amino-6-(ethylmethylamino)benzo-
nitrile with ethyl oxalyl chloride as in Example 1 gives the
product, m.p. 75-78C. ~ -
AnalySis for: C14H17N303
Calculated. C, 61.08; H, 6.22; N9 15.26
Found: C9 60.77; H, 6.21; N, 15.34
l~e amine is obtained by the usual iron reduction.
:
- 21 -
1C~6~356
2-(ethylmethylamLne)-6-nitrobenzonitrile is obtained by
displacement with ethylmethylamine, m.p. 60~63C. ~ ;
Analysis or: CloHllN302
Calculat0d: C, 58.53; H, 5 ~0; N, 20.~8 -~
Found:C, 58.84; H, 5.48; N, 20.81
E~ample 10
., .
[2-Cyano-3-(Methylisopropylamino)Phenylamino]- -
Oxoa¢etic Acid Eth~l Ester ~
v -- :
The usual oxalation as in Example 1 of 2-amino
6-(methylisopropylamino)benzonitrile gives the title
compound, m.p~ 64-67C.
Analysis for: ClsH19N303 ~`
Calculated: C, 62.26; H, 6.62; N, 14.52
Found: C, 62.30; ~, 6.65; N, 14.53
2-ami~o~6-(methylisopropylamino)benzonitrile is
obtained by iron reduction as in Example 1.
2-(methylisopropylamino)-6-nitrobenzonitrile is
obtained by the usual substitution using methylisopropylamine,
m.p. 70-72C.
Analysis for: CllH13N30
Caleulated: C, 60.26; H, 5.98; N, 19.15
Found: C, 60.21; ~I, 5.93; N, 19.19
Exam~le 11
C2-Cyano-3-~Pyrrolidinyl)Phenylamino:l- , -
'~
Oxoacetic Acid Eth~l Ester
O~alation of 2-amino-6-pyrrolidinylbenzonitrile
as in Example 1 gives the title compound, m.p. 138-141C.
:, .
Analysis for: C15H17N
Calculated: C, 62.70; H, 5.96; N, 14.63
Fou~d: C, 62.81; H, 5.98, N, 14.61
"'" :.
; ., .
- 22
`` 1~6~356 :`
"
2-amino-6-pyrrolidinylbenzonitrile is prepared
by iron reduction of the corresponding nitro deri~ative as in
Example 1, m~p. 112-114C. !`,i' .
Analysis for: CllH13N3
Calculated: C, 70.56; H, 7.00; N, 22.44
Found: C, 70.51; H, 6.71; N, 22.50
2-nitro-6-pyrrolidinylbenæonitrile is prepared by
the usual displacement (example 6) using pyrrolidine,
..
m.p.lll-113C.
. ~ ,
Analysis for: CllHllN30
Calculated:C, 60.83; H, 5010; N, 19.35
Found:C, 61.04; H, 5.14; N, 19.59
E~am~le 12 ;
~2-C~ano-3-(Morpholinyl)Phenylamino~-
i
Oxoacetic ~cid Ethyl Estsr `~
,;
This is prepared from ~-amino-6-morpholinyl-
benzonitrile and ethyloxalyl chloride in the usual manner,
m.p. 115-117C.
Analysis for: ClsH17N304
Calculated: C, 59.39; H, 5.65; N, 13.86
Found: C, 59.21; H, 4.7~; N, 13.69 ~ `
2-amino-6-morpholinylbenzonitrile is prepared b~
reduction of 2-(4-morpholin~1)-6-nitrobenzonitrile as in
Example 1, m.p. 157-160C.
Analysis for~ CllH13N30
Calculated: C, 65.00; H, 6.45; N, 20.68
Found: C, 64.81; H, 6035; N, 20.79 -~
2-(4-morpholinyl)-6-nitrobenzonitrile is pnepa~ed
by displacement with morpholine as in Example 6, m.p.
152-155C.
, .,
..
- 23 -
~6~L3~;6 ` ~
Analysis for: CllHllN303
Calculated: C, 56.65; H, 4.76; N, 18.02 ; -
Found:Cg 56.95; H, 4.82; N, 18.35
~ ,; ,
Exam~le 13 '!'.`
[2-Cyano-3-(4-Morpholinyl)Phenyl~ino~- ~
Oxoacetic Aci~ l-Methylpropyl Ester ~ -
This material is prepared as in Example 12 using
sec-butyloxalyl chloride instead of ethyl oxalyl chloride,
m.p. 108-111C.
Analysis ~or C17II21N34 ~ ~ -
Calculated: C, 61.62; H, 6.39; N, 12.68
Found: C, 61.42; H, 6.71; N, 12.95
The following sodium salts are all prepared by ;
the same procedure: -
The o~oacetic acid ethyl ester is dissolved in
ethanol at reflux, exactly one equivalent of 5.9 N sodium
hydroxide is added and the solution is allowed to cool.
The resul~ing solid is filtered, washed with e~hanol and
dried to gi~e the sodium salt.
Example 14
[2-Cyano-3-(Methylamino)phenylamino]- ;
Oxoacetic Acid Sodium Salt, 2/5 hydrate1 1/5 Ethanola~e i
m.p. 272-~75C.(dec)
Analysis ~or: CloH8N303 1/5 EtoH 2/5 H20 ;
Calculated: C, 48.49; H, 3.91; N, 16.31 `~
Found: ~, 48.70; H, 3.82; N, 16.29
Example 15 `~'
C2-Cyano-3-~EthylmethylamiIlo)Ph~ylamino]- ,, ::,
,.
Oxoacetic Aci~ Sodium Salt, 7/10 Eydrate
m.p. 90-94C.
- 2~ -
, ,.
::
, . . . . . . . . .. .. . ... . . .. ...
~(~6~356
; .
Analysis for C12~12N35Na 7/10 H20
Calculated: C, 51.14; H, 4.79; N, 14.91
Foun~: ~, 51.01; H, 4.65; N, 14~99
Exam~le 16
~3 (Butylamino)-2-Cyanophenylamino]- ;;
Oxoacetic Acid, Sodium Salt
m.p. 252-254C.
Analysis for: C13H14N303Na
Calculated: C, 55.12; H, ~.98; N, 1~.83 -~
Found: C, 54.82; H, 4.8~-; N, 14.59 !:
Example l?
C2 Cyano-3-(4-Morpholinyl)Phenylamino~-
Oxoacetic Acid, Sodium Salt, ~/lQ H~drate
m.p. 170C.(shrink), 240C.(dec.)
Analysis for: C13H12N30~Na ~/10 H20
Calculated: C, 51.28; H, 4.24; N, 13.80
Found: C, 51.35; H, 4.28; N, 13.91
Example 18
(4-Amino-2-Cyanophen~l~mino)Oxoacetic Acid Ethyl Ester
5.0 g. of (2-cyano-~-nitrophenylamino)oxoacetic
; acid ethyl ester in 150 ml. of ethanol and 0.4 g. of 10%
Pd/C is hydrogenated until hydrogen uptake ceases. The
reaction mixture is filtered through Celit~ , evaporated
to dryness and the solid is recrystalli~ed from ethanol, 4.1
g., m.p. 137-139C.
nalysiS or: c~ N3o3
I Calculated: C, 56 65; ~I, 4 76; N, 18.02
;~ Found: C, 56.49; H, 4.94; N, 18.09
., ,
,
.,.~ ,
; - 25 -
... .
.;.~. . ~ ... , . :
. . , . ~ - ~ :
.; .
~ 61356
~2-cyano-4 nitrophenyl)oxoacetic acid ethyl ester
is prepared by the usual ethyl oxalation of 2-amino-5-
nitrobenzonitrile as in Example 1, m.p. 137-319C.
Analysis for: CllHgN305
Calculated: C, 50~19; H, 3.45; N, 1~.97 ~ ~
Found: C, 49.99; H, 3.55; N, 15.98 - -
The oxalyl chloride ester employed i~ the synthesis
of the compounds of this invention is preferable the ethyl
ester, the sec-butyl ester or the cyclohexyl esterO Ho~~
ever, other simple esters are similarly applicable, producing
the corresponding ester products with unchanged biological
activity, although assimilation by the host may vary some-
what. Thus, the esters initially produced may be lower
alkyl (e.g. methyl, ethyl~ propyl, i-propyl, butyl, sec-
butyl, amyl, sec-amyl, hexyl, etc.); aralk~l (e.g. benzyl,
phenethyl, etc~); or cycloalkyl (e.g. cyclopantyl, cyclo-
hexyl, etc.). Thus, the esters produced as part of this
invention embrace esters in which the hydrocarbon moiety
of the alcohol is alkyl of 1 to 5 carbon atoms, hydro- ;;
carbonic aralkyl of 7)c~ 8 carbon atoms or cycloalkyl of
S to 6 carbon atomY.
,'
,
." . .
. .
.'~ .~,
_ 26 -
... .
